Disinfectant and method of making

ABSTRACT

A non-toxic environmentally friendly aqueous disinfectant is disclosed for specific use as prevention against contamination by potentially pathogenic bacteria and virus. The aqueous disinfectant is formulated by electrolytically generating silver ions in water in combination with a citric acid. The aqueous disinfectant may include a suitable alcohol and/or a detergent. The aqueous disinfectant has been shown to be very effective at eliminating standard indicator organisms such as staphylococcus aureus, salmonella cholerasuis and pseudomonas aeruginosa.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a divisional application of U.S. Ser. No.11/832,474, filed 1 Aug. 2007 which is a continuation of U.S. Ser. No.10/434,742, filed 9 May 2003, which a continuation of U.S. Ser. No.09/544,404, filed 6 Apr. 2000, which claims benefit under 35 U.S.C. §119(e) of U.S. Ser. No. 60/128,212, filed 7 Apr. 1999. The contents ofthese applications are incorporated herein by reference.

BACKGROUND OF THE INVENTION

1. Field Of The Invention

This invention relates to disinfectants and more particularly to anenvironmentally friendly, non-toxic aqueous disinfectant for specificuse against pathogenic bacteria and viruses.

2. Prior Art Statement

The prior art has demonstrated that the presence of copper and silverions in an aqueous solution is useful as a disinfectant. Many in theprior art have used copper and silver ions in an aqueous solution as adisinfectant in water systems such as cooling towers, swimming pools,hot water systems in hospitals, potable water systems, spa pools and thelike.

Typically, copper and silver electrodes were connected to a directcurrent power supply. When the direct current was applied to the copperand silver electrodes, copper and silver ions were generated by anelectrolysis process producing copper and silver ions within the water.In one example of the prior art, water was passed continuously throughan ion chamber having copper and silver electrodes. The water emanatingfrom the ion chamber contained the copper and silver ions generated bycopper and silver electrodes within the ion chamber. The water emanatingfrom the ion chamber containing the copper and silver ions was used as adisinfectant in water systems such as cooling towers, swimming pools,hot water systems in hospitals, potable water systems, spa pools and thelike. The copper and silver ions within the water systems acted as adisinfectant for controlling algae, viruses, bacteria and the like.

U.S. Pat. No. 3,422,183 to Ellison discloses biocide compositionscomprising ultra-violet irradiated silver fluoride solutions containingcolloidal silver resulting from the irradiation and kept in dispersionby a protective colloid, e.g. , casein or gelatin, and biocide usesthereof in slime control, against pathogens or other microbes in food orbeverage containers or processing equipment, as an ingredient of woodpreservatives, as a bactericide in paints, as a biocide in syntheticpolymer films, as a sterilant in bandages, and biocide-like uses inother areas.

U.S. Pat. No. 3,702,298 to Zsoldos discloses a method of maintaining ahighly oxidizing aqueous solution intended primarily for treatment ofswimming pool water. A metal having a multiple valence is interacted toa lower valence with oxidizable debris in the solution, and the metal iscontinuously re-oxidized to a higher valence by maintaining in the watera constant excess of an oxidizer bank consisting of a salt of a peroxyacid. Silver, copper and nickel are suitable metals and their salts havegermicidal properties which are greatly increased and the spectrumbroadened by converting the mono salt to a divalent or trivalent salt.

U.S. Pat. No. 4,180,473 to Maurer et al. discloses a method oftransporting metal ions by introducing a metal complex into a mediumcontaining a moiety which demands the metal ion and the complex releasesthe ions in a controlled manner upon demand. The metal complexes have anaqueous proton induced dissociation property represented by asigmoidally-shaped curve on a cartesian coordinate plot of the negativelog of the metal ion concentration versus the negative log of hydrogenion concentration. This dissociation property causes a controlledrelease of metal ion into mediums containing a reacting moiety upondemand for the metal ion. For example, metal working emulsions of oiland water are stabilized by the addition thereto of minor amounts of ametal complex, e.g. disodium monocopper (II) citrate, which at alkalinepH metalworking conditions above about 7 to about 9 releases metalcations to the emulsions imparting stabilizing characteristics whichprevent emulsion degradation by a number of factors commonly encounteredin metalworking operations. Also, the method is effective in thecontrolled release of metal ions in the normal range of physiologicalpH, i.e. about 4 to 9, for growth controlling action againstmicroorganisms including bacteria, fungi and viruses.

U.S. Pat. No. 4,291,125 to Greatbatch discloses a method and apparatusfor killing plant and animal bacteria and plant viroids by electricallygenerated silver ions. The silver ions serve as germicidal agents ininfection control and are generated by very slow electrical anodiccorrosion of a silver wire located closely adjacent the infection site.In particular, a silver anode and a cathode of non-corroding metal arelocated in an electrolytic nutrient medium with the silver anode beingwithin five millimeters of the infection site, and a direct voltage isapplied to the anode and cathode in a manner passing a positive currentin the microampere range into the silver anode causing it to corrodeslightly and give off silver ions which produce a germicidal environmentabout the infection site.

U.S. Pat. No. 4,385,632 to Odelhog discloses an absorbent body forcollecting blood, feces and urine containing a water-soluble copper saltwhich impedes bacterial growth, prevents the breaking-down of urea intoammonia and complex-binds ammonia so as to prevent the occurrence ofunpleasant odor. Preferably copper acetate is used, in which even theacetate ion has germicidal effect.

U.S. Pat. No. 4,564,461 to Skold et al. discloses mechanical working ofcast iron performed in the presence of an aqueous metal workingcomposition containing an organic copper (II) complex and an ironcorrosion inhibitor. An aqueous concentrate, which after dilution withwater is suitable for application in mechanical working of cast iron,contains 1-50% copper (II) complex with such a Cu₂+ content of 0.5-20%,1-50% iron corrosion inhibitor, 0-50% lubricant, 0-20% pH-regulators,bactericides and solubilizing agents and 10-70% water.

U.S. Pat. No. 4,608,183 to Rossmoore discloses antimicrobial mixtures ofisothiazolones and a metal complex with a polyfunctional ligand whichare synergistic. The mixtures particularly include mixtures of amonocopper disodium citrate as the ligand and a 5-x-2-lower alkyl4-isothiazolin-3-one wherein x is a halo or hydrogen group as theisothiazolone. The compositions are particularly useful for metalcutting fluids wherein long duration antimicrobial activity is desired.

U.S. Pat. No. 4,666,616 to Rossmoore discloses synergisticanti-microbial compositions containing a mixture of a metal complex of apolyfunctional organic liquid and a biocidal composition which containsor releases a lower aldehyde containing 1 to 5 carbon atoms. Thecompositions are particularly useful as metal working fluids at alkalinepH and have a broad spectrum of activity against fungi and bacterial.

U.S. Pat. No. 4,708,808 to Rossmoore discloses synergisticanti-mircrobial compositions containing a mixture of a metal complex ofa polyfunctional organic ligand and a biocidal composition whichcontains or releases a lower aldehyde containing 1 to 5 carbon atoms.The compositions are particularly useful as metal working fluids atalkaline pH and have a broad spectrum of activity against fungi andbacteria.

U.S. Pat. No. 4,780,216 to Wojtowicz discloses a sanitizing compositionconsisting essentially of a mixture of a calcium hypochlorite compoundand a peroxydisulfate compound having the formula: M_(x)S₂O₈ where M isan alkali metal or alkaline earth metal, and x is 1 or 2 is employed intreating water to improve pH control and provide increased removal oforganic materials. The compositions provide improved sanitation of waterin swimming pools, spas, and cooling towers by efficiently oxidizingorganic impurities while helping to minimize the increase in the pH ofthe water. This permits a reduction in the amount and frequency ofaddition of acidic compounds such as hydrochloric acid to the waterbodies. Further, the incorporation of additives such as algaecides,dispersant, and clarifying agents provides for significant improvementsin water quality as evidenced by sparkling pure water.

U.S. Pat. No. 4,915,955 to Gomori discloses a concentrate with anunlimited shelf-life, which can be mixed with hydrogen peroxide at aratio of 1:99 to 1:199 to become an effective disinfectant, is obtainedwhen a viscous solution of inorganic acid, with a pH less than or equalto 1.6, is mixed with a silver salt compound or a colloidal silvercompound at 50° to 66° C. The mixture is further combined at roomtemperature with other inorganic acid(s) to reach a total of 100 ginorganic acid(s) per liter of water at room temperature, an organicacid stabilizer is added and the mixture is homogenized. Theconcentrate, during storage, remains homogeneous and crystal-clear.

U.S. Pat. No. 4,933,178 to Capelli discloses a medical device with anantimicrobial coating that is safe, effective, photostable and readilymanufacturable produced by applying a composition to at least one bodyfluid-contacting surface of the device such that a solid coating isprovided on that surface, the coating composition comprising anoligodynamic metal salt of a sulfonylurea, a polymeric material, atleast one acid compound selected from the group consisting of awater-soluble carboxylic acid and water-insoluble carboxylic acid, and acarrier liquid in which foregoing components are soluble. Theantimicrobial coating accommodates variation in the release ofantimicrobial metal ions as a function of the intended use for a medicaldevice to which the coating is applied.

U.S. Pat. No. 5,017,295 to Antelman discloses a method or methods ofcontrolling the growth of bacteria in the water of swimming pools and/orindustrial water supplies by adding to the water a specifiedconcentration of a stable divalent silver compound. The invention hasthe advantage over chlorination in that it is odorless and non-volatile.It furthermore is superior to monovalent silver compounds as thesecompounds do not decompose in the presence of light and resistprecipitation by halides and form divalent soluble complexes which inthe monovalent state are invariably insoluble solids.

U.S. Pat. No. 5,073,382 to Antelman discloses a solid alkalinebactericidal composition suitable for compounding alkaline end productssuch as food and dairy cleaners and surgical scrubbing soaps, formed bythe neutralization of acid stabilized inorganic divalent silvercomplexes and capable of effecting 100% kills upon cultures of anaerobicbacteria colonies of 100 K/cc. within 5 minutes.

U.S. Pat. No. 5,078,902 to Antelman discloses divalent silver halidesproviding a source for divalent bactericidal silver ions in the presenceof persulfate. The halides are especially effective when applied towater used in industrial cooling installations, hot tubs and swimmingpools and will conform to stringent EPA requirements for waters utilizedfor bathing as in tubs and pools of 100% kills of 100 K/cc E. Colicoliforms within 10 minutes, exemplary of which are the chloride andbromide which give 100% kills within 5 minutes. The halides, of course,can be used in salty water since they are solids immune from halideaction that would otherwise precipitate soluble divalent silver fromsolution.

U.S. Pat. No. 5,089,275 discloses solid bactericidal compositions basedon divalent silver (Ag(II)) as the active sanitized agent. Thecompositions are prepared by reacting acid liquid Ag(II) complexes withanhydrous calcium sulfate so as to form a solid matrix in which thebactericide is entrapped in the resulting hydrated calcium sulfate. Theoptimum compositions are described consisting of Ag(II) of solid (byweight) to liquid (by volume) being 5:2. The resulting solidbactericides can be used in water cooling installations. They arecapable of causing 100% kills within 10 minutes of E. Coli conforms inconformity with EPA protocols, allowing them to qualify as swimming pooland hot tub sanitizers. Since the compositions are based on calciumsulfate, they are also suitable as mineralizers, thus providing a dualfunction.

U.S. Pat. No. 5,332,511 to Gay et al. discloses a process for sanitizingwater in swimming pools, spas and hot tubs whereby the level of bacteriain said water is lowered comprising treating said water with abactericidal effective amount of a combination of diisodecyl dimethylammonium chloride and copper (II) ions, the concentration of diisodecyldimethyl ammonium chloride in said water being less than about 60 partsper million parts of water by weight and treating said water at leastintermittently with an oxidant selected from the group consisting ofavailable chlorine and ozone.

U.S. Pat. No. 5,364,649 to Rossmoore et al. discloses activity ofantimicrobial compounds selected from isothiazolones and compounds whichrelease formaldehyde enhanced with a metal complex of a loweralkanolamine, particularly copper (cupric) trietha-iolamine. Theenhancement is particularly useful in metalworking fluids.

U.S. Pat. No. 5,373,025 to Gay discloses a sanitizer compositioncomprising a bactericidal effective amount of the combination of (a) aquaternary ammonium compound selected from the group consisting of(hydrogenated tallow) 2-ethylhexyl dimethyl ammonium salt, dicocodimethyl ammonium salt, and mixtures thereof; and (b) a copper (II) ionsource.

U.S. Pat. No. 5,382,337 to Wlassics et al. discloses a process foroxidizing organic materials or compounds in aqueous phase, with hydrogenperoxide and in the presence of ferrous ions Fe-(II), and optionallycupric ions Cu-(II), carried out under irradiation with artificialvisible light.

U.S. Pat. No. 5,464,559 to Marchin et al. discloses a compositionprovided for treating drinking water for disinfecting and/or removingiodide. The composition utilizes resin bound silver ions. For performingthe disinfection or iodide removal with minimal release of silver ionsinto the water being treated, a chelating resin having iminodiacetatechelating groups is employed, and the resin is loaded with not over 0.5mole of silver ions per mole of iminodiacetate.

U.S. Pat. 5,503,840 to Jacobson et al. discloses an antimicrobialcomposition of titanium dioxide, barium sulfate, zinc oxide particles,and mixtures thereof having successive coatings of silver, in some casesa coating of zinc and/or copper compounds such as zinc oxide, copper(II) oxide and zinc silicate; silicon dioxide; alumina; and a dispersionaid such as dioctyl azelate.

U.S. Pat. 5,510,109 to Tomioka et al discloses an antibacterial andantifungal composition which comprises an antibacterial and antifungalmaterial carried on a porous particle carrier. Preferably, the porousparticle carrier is a silica gel particle. The antibacterial andantifungal material is at least one metal complex salt, and can containplant extracts and the like in addition to the metal complex salt. Atleast a portion of the surface of the above-mentioned carrier having theantibacterial and antifungal composition can be coated with a coatingmaterial.

Unfortunately, these copper and silver ions within an aqueous solutionhave only a limited stable ionic life. After a limited time, the copperand silver ions form complexes with other elements thus diminishing theconcentration of the copper and silver ions within the aqueous solution.Accordingly, the aqueous solution had to be replenished with copper andsilver ions to maintain the concentration of the copper and silver ionswithin the aqueous solution. The aqueous solution may be replenishedwith copper and silver ions by constantly circulating the aqueoussolution thorough the ion chamber.

In my prior U.S. patent application Ser. No. 09/169,229 filed 9 Oct.1998 and Internation application PCT/US98/121604, I disclosed an aqueousdisinfectant solution having a stable ionic form having an extendeduseful shelf-life. The extended useful shelf-life of the disinfectant ofthe present invention enables the disinfectant to be packaged in anaqueous concentrate form. The extended useful shelf-life of the aqueousdisinfectant solution enables the aqueous disinfectant solution to bepackaged in an aqueous concentrate form.

It is an object of the present invention to expand upon my priorinvention by providing an improved disinfectant and the method of makingcomprising an aqueous disinfectant for specific use as preventionagainst contamination by potentially pathogenic bacteria and virus andantifungal properties.

Another object of this invention is to provide an improved disinfectantand the method of making which is an effective disinfectant foreliminating standard indicator organisms such as staphylococcus aureus,salmonella cholerasuis and pseudomonas aeruginosa.

Another object of this invention is to provide an improved disinfectantand the method of making which is a non-toxic, environmentally friendlyaqueous disinfectant.

Another object of this invention is to provide an improved disinfectantand the method of making which comprises a stable ionic formulationhaving an extended useful shelf-life.

Another object of this invention is to provide an improved disinfectantand the method of making which may be packaged in a concentrated aqueousform.

Another object of this invention is to provide an improved disinfectantand the method of making which may be electrolytically generated in abatch process or a continuous process.

Another object of this invention is to provide an improved disinfectantand the method of making which is electrolytically generated in aneconomical manner.

Another object of this invention is to provide an improved disinfectantand the method of making which is suitable for use with an .alcoholand/or a detergent.

Another object of this invention is to provide an improved disinfectantand the method of making which may be used on exposed and/orcontaminated surfaces to kill bacteria, virus, fungi and othermicro-organisms.

Another object of this invention is to provide an improved disinfectantand the method of making which may be used on contaminated open woundsand tissue, dermal wound sites and/or lesions of living organisms suchas animals and humans.

Another object of this invention is to provide an improved disinfectantand the method of making which may be used on exposed surfaces in foodprocessing plants, residential, hospital, restaurants, public facilitiesand the like.

Another object of this invention is to provide an improved disinfectantand the method of making which may be used to control bio-film,microbes, algae and the like.

Another object of this invention is to provide an improved disinfectantand the method of making which may be used to control microbes in or onagricultural and food items and drinking water.

Another object of this invention is to provide an improved disinfectantand the method of making which may be used to control microbes in paintadditive for mildew control in paints.

The foregoing has outlined some of the more pertinent objects of thepresent invention. These objects should be construed as being merelyillustrative of some of the more prominent features and applications ofthe invention. Many other beneficial results can be obtained by applyingthe disclosed invention in a different manner or modifying the inventionwith in the scope of the invention. Accordingly other objects in a fullunderstanding of the invention may be had by referring to the summary ofthe invention, the detailed description describing the preferredembodiment in addition to the scope of the invention defined by theclaims taken in conjunction with the accompanying drawings.

SUMMARY OF THE INVENTION

A specific embodiment of the present invention is described and shown inthe attached Detailed Description. For the purpose of summarizing theinvention, the invention relates to an improved non-toxicenvironmentally friendly aqueous disinfectant for use as a preventionagainst contamination by potentially pathogenic bacteria, virus andfungi. The improved aqueous disinfectant is suitable for use on exposedsurfaces. In addition, the improved aqueous disinfectant is suitable foruse on dermal wound sites and lesions of living organisms such asanimals and humans. The aqueous disinfectant pH varies from 2 to 7.

The aqueous disinfectant is incorporated into an aqueous solution ofsilver ion organic acid complex wherein the silver is electrolyticallygenerated in a solution of the organic acid and water. Theelectrolytically generated silver forms an organic metal complex withthe organic acid. In one example of the invention, the electrolyticallygenerated silver forms a complex with the organic acid of(Ag(CO)x)+(OA)−, wherein OA is an organic acid selected from a group oforganic acids having the characteristic of an acid as well as thecharacteristic of an alcohol. In another example of the invention, theelectrolytically generated silver forms a complex with the organic acidof (Ag(CO)x)+(OA)−, wherein OA is an organic acid selected from a groupconsisting of ascorbic acid, citric acid, glycollic acid, lactic acid,maleic acid, tartaric acid. In a further example of the invention, theelectrolytically generated silver forms a complex with the organic acidof (Ag(CO)x)+(OA)−, wherein OA is an organic acid selected from a groupconsisting of acetic acid, aspartic acid, cis-cyclohexane dicarboxylicacid, chloracetic acid, dl-cysteine acid, dl-cyctine acid, malic,malonic acid, propionic acid, succinic acid.

The aqueous disinfectant may be combined with an alcohol such as ethylalcohol (EtOH) and/or a detergent such as sodium dodecyl sulfate.

The invention is also incorporated into the process of making thedisinfectant comprising the step of electrolytically generating silverin a solution of organic acid and water to form an aqueous solution ofthe silver organic acid. The process may include creating a solution ofapproximately 2% or greater organic acid in water by volume. A positivesilver electrode is spaced relative to a negative electrode for enablingthe solution to be located therebetween. A potential difference isapplied to the positive and negative electrodes to establish a flow ofsilver ions between the positive and negative electrodes for enablingthe silver ions to react with the organic acid to form silverion-organic acid complex thereby.

The invention is also incorporated into the process of making silver ionorganic acid complex, comprising the step of electrolytically generatingsilver in a solution of an organic acid and water to formed an aqueoussolution of the silver ion organic acid complex.

The foregoing has outlined rather broadly the more pertinent andimportant features of the present invention in order that the detaileddescription that follows may be better understood so that the presentcontribution to the art can be more fully appreciated. Additionalfeatures of the invention will be described hereinafter which form thesubject of the invention. It should be appreciated by those skilled inthe art that the conception and the specific embodiments disclosed maybe readily utilized as a basis for modifying or designing otherstructures for carrying out the same purposes of the present invention.It should also be realized by those skilled in the art that suchequivalent constructions do not depart from the spirit and scope of theinvention.

BRIEF DESCRIPTION OF THE DRAWINGS

For a fuller understanding of the nature and objects of the invention,reference should be made to the following detailed description taken inconnection with the accompanying drawings in which:

FIG. 1 is a diagram of a first process of making the disinfectant of thepresent invention;

FIG. 2 is a diagram of a second process of making the disinfectant ofthe present invention;

FIG. 3 is an enlarged detailed view of the ion chamber of FIGS. 1 and 2;and

FIG. 4 is an enlarged detailed view of an ion chamber suitable formaking the disinfectant of the present invention in a batch process.

Similar reference characters refer to similar parts throughout theseveral Figures of the drawings.

DETAILED DISCUSSION Process of Making

FIG. 1 is a diagram of a first process 10 of making the disinfectant 14of the present invention. The first process 10 is shown as a continuousprocess of making the disinfectant 14. It should be understood that thefirst process 10 of FIG. 1 is only an example of a process and numerousother variations and/or processes may be utilized to make thedisinfectant 14 of the present invention.

The disinfectant 14 may be used immediately for any suitable applicationsuch as a disinfectant in a water system including cooling towers, hotwater systems, potable water systems, or any other suitable applicationor surface.

The first process 10 comprises a water input conduit 16 for introducingwater 18 from a water source (not shown) to a water treatment unit shownas a reverse osmosis unit 20. The reverse osmosis unit 20 passes thewater 18 from the water input conduit 16 through a semi-permeablemembrane (not shown) for removing impurities from the water. Althoughthe water treatment unit is shown as a reverse osmosis unit 20 it shouldbe understood that various water treatment units may be employed withinthe process shown in FIG. 1. Preferably, the water 18 emanating from thereverse osmosis unit 20 is deionized medically pure water.

The water 18 emanating from the reverse osmosis unit 20 is directed to avalve 30 through a conduit 31. The valve 30 directs the water 18 thougha conduit 32 to a flow control injector 40. An organic acid tank 50contains concentrated organic acid. The concentrated organic acid isdirected by a conduit 51 to a metering valve 60 for metering theconcentrated organic acid into the flow control injector 40. The flowcontrol injector 40 mixes the concentrated organic acid with the water18 to provide a dilute organic acid solution 62. The metering valve 60controls the concentration of the organic acid within the water 18. Thediluted organic acid solution 62 is directed by a conduit 62 into an ionchamber 70.

FIG. 3 is an enlarged detailed view of the ion chamber 70 of FIG. 1. Theion chamber 70 includes a positive and a negative electrode 71 and 72.The positive and negative electrodes 71 and 72 are located in a spacedapart position for enabling the diluted organic acid solution 62 to passbetween the positive and negative electrodes 71 and 72. Each of thepositive and negative electrodes 71 and 72 is fabricated from elementalsilver. Preferably, the positive and negative electrodes 71 and 72 areformed from 99.9999% pure elemental silver.

A direct current power supply 80 includes a positive and a negativeconductor 81 and 82 connected to the positive and negative electrodes 71and 72. The positive and negative electrodes 71 and 72 are spaced aparta suitable distance such as 2.0 to 8.0 centimeters to allow an ioniccurrent flow between the positive and negative electrodes 71 and 72.

Upon energizing the direct current power supply 80, an ion current flowsbetween the positive and negative electrodes 71 and 72. The direct ioncurrent flow between the positive and negative electrodes 71 and 72produces electrolytically free silver ions within the diluted organicacid solution 62. The silver ions react with the organic acid in thediluted organic acid solution 62 to produce the disinfectant 14 of thepresent invention.

The disinfectant 14 is directed by a conduit 86. to a settling tank 90.The settling tank 90 includes an overflow conduit 91 and a drain conduit92. The disinfectant 14 exits the settling tank 90 through the overflowconduit 91. Any precipitated materials from the disinfectant 14 withinthe settling tank 90 fall to the bottom of the settling tank 90. Theprecipitated materials at the bottom of the settling tank 90 may beremoved through the drain conduit 92 to a purge tank 100. Theprecipitated materials in the purge tank 100 may be recycled.

The disinfectant 14 exiting through the overflow conduit 91 from thesettling tank 90 is directed to a particle filter 110. Although theparticle filter 110 may be any suitable filter, preferably the particlefilter 110 is a submicron filter. The filtered disinfectant 14 isdirected to a valve 120 by a conduit 121. The valve 120 directs thefiltered disinfectant 14 to a conduit 122 for discharge from the firstprocess 10.

The filtered disinfectant 14 discharged from conduit 122 may be usedimmediately for any suitable application such as a disinfectant in awater system or any other suitable application. In the event a greaterconcentration of the disinfectant 14 is desired, the disinfectant 14 maybe recirculated for increasing the concentration of the disinfectant 14.

FIG. 2 is a diagram of a second process 10A of making the disinfectant14 of the present in a concentrated form. The second process 10A isshown as a recirculating process of making the disinfectant 14 and forincreasing the concentration of the disinfectant 14. In the concentratedform, the disinfectant 14 may be bottled for use at a later time. Itshould be understood that the second process 10A of FIG. 2 is only anexample of a process and numerous other variations and/or processes maybe utilized to make the disinfectant 14 of the present invention.

In the second process 10A shown in FIG. 2, the valve 30 and 120 aremoved into positions opposite to the positions shown in FIG. 1. Thevalve 120 directs the filtered disinfectant 14 to a conduit 123. Theconduit 123 is connected through a conduit 130 to the conduit 32 of thevalve 30.

The valve 30 directs the filtered disinfectant 14 though the conduit 32to the flow control injector 40. Additional concentrated organic acid isdirected through the metering valve 60 into the flow control injector40. The flow control injector 40 mixes the concentrated organic acidwith the filtered disinfectant 14 to increase the concentration of theorganic acid solution 62A.

The organic acid solution 62A is directed into an ion chamber 70 toproduce additional silver ions within the organic acid solution 62A. Thesilver ions react with the organic acid in the organic acid solution 62Ato increase the concentration of the disinfectant 14. The disinfectant14 is passed through the settling tank 90 to exit through the overflowconduit 91. The disinfectant 14 is filtered by the particle filter 110and is directed to the valve 120 by the conduit 121.

The valve 30 and 120 are maintained in positions shown in FIG. 2 tocontinue to recirculate the disinfectant 14 for increasing theconcentration of the disinfectant 14. Upon obtaining the desiredconcentration of the disinfectant 14, the valve 120 may be moved to theposition shown in FIG. 1 to discharge the disinfectant 14 from theconduit 122.

FIG. 4 is an enlarged detailed view of an ion chamber 170 suitable formaking the disinfectant of the present invention in a batch process. Theion chamber 170 includes a positive and a negative electrode 171 and172. Each of the positive and negative electrodes 171 and 172 isfabricated from 99.9999% pure elemental silver.

The positive and negative electrodes 171 and 172 are located in a spacedapart position for enabling the organic acid solution 162 to passbetween the positive and negative electrodes 171 and 172. Preferably,the positive silver electrode 171 is spaced relative to a negativeelectrode 172 a distance sufficient to enable silver ion flowtherebetween. The spacing of the positive and negative electrodes 171and 172 has been shown in an exaggerated fashion in FIG. 4. Preferably,a spacing of approximately 2.0 to 8.0 mm. has been found to be suitablefor the above concentration of organic acid and water.

A direct current power supply 180 includes a positive and a negativeconductor 181 and 182 connected to the positive and negative electrodes171 and 172. Upon energizing the direct current power supply 180, an ioncurrent flows between the positive and negative electrodes 171 and 172.The direct ion current flow between the positive and negative electrodes171 and 172 produces electrolytically free silver ions within theorganic acid solution 162. The silver ions react with the organic acidin the organic acid solution 162 to produce the disinfectant 14 of thepresent invention.

The process of making a disinfectant comprises electrolyticallygenerating silver ions in a solution of organic acid and water to forman aqueous solution of silver ion organic acid complex. Preferably, thesolution of organic acid and water comprises a solution of approximately5.0% to 10% organic acid in water by volume. A potential difference of12 volts to 50 volts provides a flow of silver ions in the range of 0.1amperes to 0.5 amperes per square inch. A more fuller explanation of thecontent of the solution within the ion chamber 170 will be described ingreater detail hereinafter.

The prior art has established in that the generation of both silver ionsand copper ion in water provides the best disinfectant properties. Thecombination of silver ions and copper ions provides superiordisinfecting properties than either silver ions alone or copper ionsalone. This synergistic effect of silver ions and copper ions in waterhas been well established by the prior art.

In contrast to this established prior art, the disinfectant of thepresent invention is formed in a solution of organic acid and waterrather than water alone. Additionally, the disinfectant of the presentinvention has superior properties with only silver ions alone ratherthan the combination of both silver ions and copper ions. The silverions of the present process react with the organic acid to form thesilver ion organic acid complex. The silver ion organic acid complexprovides superior disinfectant properties over the prior art process ofgenerating silver and copper ions in water.

In further contrast to the established prior art, the disinfectant ofthe present invention has a stable ionic form having an extended usefulshelf-life. The useable shelf-life of the disinfectant of the presentinvention enables the aqueous disinfectant solution to be packaged in anaqueous concentrate form.

SPECIFIC COMPOSITION

In my prior U.S. patent application Ser. No. 09/169,229 filed 9 Oct.1998 and Internation application PCT/US98/21604, I disclosed an aqueousdisinfectant solution of silver organic acid complex wherein the silveris electrolytically generated in a solution of organic citric acid andwater. An aqueous disinfectant solution of silver citrate has beentested and found to be a stable ionic form having an extended usefulshelf-life. The extended useful shelf-life of the disinfectant enabledthe disinfectant to be packaged in an aqueous concentrate form.

Concentrations of 0.7% by volume have been formulated in accordance withthe above process. A concentration of 0.7% silver citrate by volumecorresponds to 7000 parts per million (ppm). The concentration of 0.7%silver citrate was formed in a solution of organic acid and watercomprises approximately 20-30% organic acid by volume. Higherconcentration of the silver citrate in the range of 2.0% or greater byvolume are believed to be obtainable by the above process. It appearsthe higher the concentration of organic acid in water, the higher theconcentration of silver citrate formed by the above process. The aboveweight/volume may be a weight/weight depending on whether the componentsare solid/liquid or solid/solid.

The silver citrate was found to be stable in a concentration of 5.0% and10% citric acid solutions. The stability of the silver citrate in the1.0% citric acid solution experienced significant reductions instability. The minimum concentration of the citric acid solution istherefore some value greater than 1.0%. The maximum concentration of thecitric acid in the aqueous solution has not been determined by test.However, it is believed that the maximum concentration of the citricacid in the aqueous solution will be much greater than 10.0%. It is alsoevident from these results, that the higher the concentration of thecitric acid in the aqueous solution, the greater the concentration ofsilver ions that can be stabilized.

Nuclear magnetic resonance tests (1H NMR) were preformed on the silvercitrate formed in accordance with the above process and a blank organicacid sample. The samples showed an overwhelming excess of organic acid,with little or no other anions present. It is postulated the Ag must bein the form of the cation Ag+ complexed with the organic acid. It istheorized the empty 5 s orbital of Ag+ overlaps with the delocalized πbond on one of the carboxyl groups of organic acid. The organic acidanion is the counterion for this complex ion (Ag(OA)x)+ i.e. (OA)−.Another possibility is a zwitterion, where the negative charge is on thecomplex itself, (Ag+CA−) where the total charge of the complex isneutral. Either or both of these species may exist in the silver ionorganic acid complex formed in accordance with the above process.Multiple complexation to Ag+ is also possible.

The complete results of silver organic acid complex with the organicacid being citric acid is set forth in my prior U.S. patent applicationSer. No. 09/169,229 filed 9 Oct. 1998 and International applicationPCT/US98/121604, which is hereby incorporated by reference into thepresent application as if fully set forth herein.

OTHER ORGANIC ACIDS

The present invention expands upon the acids suitable for use forforming the silver ion organic acid complex of the present invention.The silver is electrolytically generated in a solution of the organicacid and water. In a first example of the invention, the organic acidselected from a group I consisting of ascorbic acid, citric acid,glycollic acid, lactic acid, malic acid and/or tartaric acid.

In a second example of the invention, the organic acid selected from agroup II consisting of acetic acid, aspartic acid, cis-cyclohexanedicarboxylic acid, chloracetic acid, malic, malonic acid, propionic acidand/or succinic acid and the amino acids dl-cysteine and cystine.

In a third example of the invention, the organic acid selected from agroup III consisting of amino acids, dl-cysteine and dl-cystine.

The group I consisting of ascorbic acid, citric acid, glycollic acid,lactic acid, maleic acid, tartaric acid are organic acids having thecharacteristic of an acid as well as the characteristic of an alcohol.The group II consisting of acetic acid, aspartic acid, cis-cyclohexanedicarboxylic acid, chloracetic acid, malic, malonic acid, propionic acidand/or succinic acid and the amino acids dl-cysteine and cystine areorganic acids having the characteristic of an acid. The group IIIconsisting of amino acids, dl-cysteine and dl-cystine have differentcharacteristics than Group I and Group II.

ENHANCED FORMULATIONS

An enhanced formulation of the improved disinfectant of the presentinvention includes the addition of an alcohol. In one example of thesecond formulation of the improved disinfectant, ethyl alcohol (ETOH) isadded in an approximate amount of 20% by volume. However, it should beunderstood that other types of alcohols may be added to the secondformulation of the improved disinfectant of the present invention.

Another enhanced formulation of the improved disinfectant of the presentinvention includes the addition of a detergent. In one example of thethird formulation of the improved disinfectant, sodium dodecyl sulfateis added in an approximate amount of up to 2% by volume.

The present disclosure includes that contained in the appended claims aswell as that of the foregoing description. Although this invention hasbeen described in its preferred form with a certain degree ofparticularity, it is understood that the present disclosure of thepreferred form has been made only by way of example and that numerouschanges in the details of construction and the combination andarrangement of parts may be resorted to without departing from thespirit and scope of the invention.

1. An aqueous disinfectant, comprising: an aqueous solution of silverion organic acid complex and an organic acid, wherein said disinfectantis prepared by electrolytically generating silver ion in a solution ofat least 2% wt/vol of the organic acid in water.
 2. The aqueousdisinfectant of claim 1 generated in a solution of at least 5.0% wt/volof the organic acid in water.
 3. The aqueous disinfectant of claim 1generated in a solution of at least 10.0% wt/vol of the organic acid inwater.
 4. The aqueous disinfectant of claim 1 which further contains atleast one alcohol.
 5. The aqueous disinfectant of claim 4 wherein thealcohol is ethanol and is present at approximately 20% by volume.
 6. Theaqueous disinfectant of claim 1 which further contains at least onedetergent.
 7. The aqueous disinfectant of claim 6 wherein the detergentis sodium dodecyl sulfate in an amount of up to 2% by volume.
 8. Anaqueous disinfectant, comprising: an aqueous solution of silver ionorganic acid complex and an organic acid, wherein said disinfectant isprepared by electrolytically generating silver ion in a solution of theorganic acid in water, and wherein the organic acid is selected from thegroup consisting of ascorbic acid, glycolic acid, lactic acid, malicacid, tartaric acid, aspartic acid, cyclohexane dicarboxylic acid,chloroacetic acid, malonic acid, propionic acid, succinic acid, cysteineor cystine.
 9. The disinfectant of claim 8 wherein the organic acid isascorbic acid, glycolic acid, lactic acid, malic acid, malonic acid ortartaric acid.
 10. The aqueous disinfectant of claim 8 which furthercontains at least one alcohol.
 11. The aqueous disinfectant of claim 10wherein the alcohol is ethanol and is present at approximately 20% byvolume.
 12. The aqueous disinfectant of claim 8 which further containsat least one detergent.
 13. The aqueous disinfectant of claim 12 whereinthe detergent is sodium dodecyl sulfate in an amount of up to 2% byvolume.